The firm’s employees didn’t know anything was amiss until mid-October, when three men charged into Blackfield’s offices in an upscale complex along the Moscow River in central Moscow, said people who were there.

The men, who didn’t identify themselves, said they were looking for Blackfield’s 29-year-old founder, Kim Karapetyan, according to the people who were there.

But Mr. Karapetyan wasn’t in the office that day or the next, when senior executives explained to the staff of about 50 that there was no longer any money to pay their salaries, said one former senior executive and ex-employees. The executives disclosed that all the money in the company accounts—some $20 million, including investor cash—was also missing, they said. It couldn’t be determined whether investors were from Russia or other countries.

“Our CEO just … disappeared,” said Sergey Grebenkin, one of the firm’s software developers, in an interview.

No attempts to contact or find Karapetyan were successful, and he is still MIA. The company’s website brags that its “systematic investment process helps avoid human-factor, cognitive-biases, and emotional-trading errors,” but the CEO running away with all your money seems like a fairly big human error.